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ONTOLOGY REPORT - ANNOTATIONS


Term:Microcephaly
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Accession:HP:0000252 term browser browse the term
Definition:Head circumference below 2 standard deviations below the mean for age and gender.
Comment:Head circumference is measured from just above the glabella (the most prominent point on the frontal bone above the root of the nose) to the most posterior prominent point of the occipital bone using a tape measure. Some standard charts are organized by centiles [Hall et al. [2007]], others by standard deviations [Farkas, [1981]]. It is important to add an indication of how far below the normal standard the head circumference is if an accurate assessment of this can be made. Microcephaly is an absolute term. The term relative microcephaly can be used when the head size centile is less than the centile for height, for example, head size at the 3rd centile with height at the 75% for age and sex. On prenatal ultrasound, microcephaly is diagnosed if the head circumference or the biparietal diameter is more than three standard deviations below the mean.
Synonyms:exact_synonym: Abnormally small cranium;   Abnormally small skull;   Decreased size of cranium;   Decreased size of skull;   Reduced head circumference;   Small head circumference;   decreased circumference of cranium;   small calvarium;   small cranium
 broad_synonym: Abnormally small head;   Decreased size of head;   small head;   small skull
 alt_id: HP:0001366;   HP:0005485;   HP:0005489;   HP:0005497
 xref: Fyler:4310;   SNOMEDCT_US:271611007;   UMLS:C0424688


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Path 1
Term Annotations click to browse term
  Human phenotype 0
    Phenotypic abnormality 0
      Abnormality of the nervous system 0
        Abnormality of nervous system morphology 0
          Morphological abnormality of the central nervous system 0
            Aplasia/Hypoplasia involving the central nervous system 0
              Aplasia/Hypoplasia of the cerebrum 0
                Microcephaly 0
                  Congenital microcephaly 0
                  Postnatal microcephaly + 0
Path 2
Term Annotations click to browse term
  Human phenotype 0
    Phenotypic abnormality 0
      Abnormality of the nervous system 0
        Abnormality of nervous system morphology 0
          Morphological abnormality of the central nervous system 0
            Abnormality of brain morphology 0
              Abnormality of forebrain morphology 0
                Abnormality of the cerebrum 0
                  Aplasia/Hypoplasia of the cerebrum 0
                    Microcephaly 0
                      Congenital microcephaly 0
                      Postnatal microcephaly + 0
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RGD is funded by grant HL64541 from the National Heart, Lung, and Blood Institute on behalf of the NIH.